Method and means for employing industrial trucks

ABSTRACT

854,494. Masked lift trucks. CLARK EQUIPMENT CO. Sept. 8, 1958 [Nov. 18, 1957], No. 28695/58. Addition to 806,963. Class 78 (3). In a masted lift truck, provided with a load carrier 18 pivoted to the joint 120 of a pair of levers 10, 12, the free ends of which are pivoted to members 14, 16 each movable along guides 22 on the lifting carriage, as described in the parent Specification, means are provided for selectively coupling the load carrier to either lever independently of the means for moving the members 14, 16 along the guides 22. The levers 10, 12 are each provided with a rectangular opening 140, 142, respectively, in which is mounted a locking cylinder 146 comprising a pair of pistons 150, Fig. 7, having piston-rods 152 which are urged outwardly by means of a spring 156 and which are retracted by supplying hydraulic fluid through a pipeline 158. To lock the load carrier to lever 10, the corresponding piston-rods 152 are retracted and lugs 122, 126 on the load carrier are engaged in slots in the lever 10 to bring slots in the lugs into alignment with the piston-rods 152 which are then extended by means of the spring 156 on releasing the fluid pressure in the pipeline 158. The supply of fluid pressure to the locking-cylinders 146 is controlled by valves adjacent to valves for controlling rams 62, 64, and 66, 68 which move the members 14, 16 on rollers along the guides 22. The cylinders 64, 68 move along pistonrods 62, 66, respectively, and are provided with pulleys over which pass cables connected between fixed points and the members 14, 16. The mast assembly of the truck is as described in Specification 818,457, and the forks 20 are adjustably mounted on the load carrier 18, as described in Specification 802,614.

July 19, 1960 H. WENDT 2,945,610

METHOD AND MEANS FOR EMPLOYING INDUSTRIAL TRUCKS Filed Oct. 29, 1956 6 Sheets-Sheet 1 FIG. I

HERMANN WENDT ATTY.

July 19, 1960 H. WENDT 2,945,610

METHOD AND MEANS FOR EMPLOYING INDUSTRIAL TRUCKS Filed Oct. 29, 1956 e Sheets-Sheet 2 FIG. IA

5O INVENTOR.

HERMANN WENDT ATTY.

H. WENDT July 19, 1960 METHOD AND MEANS FOR EMPLOYING INDUSTRIAL TRUCKS 6 Sheets-Sheet 3 Filed Oct. 29, 1956 FIG. 2

INVENTOR.

HERMANN WENDT July 19, 1960 H. WENDT 45, 1

METHOD AND MEANS FOR EMPLOYING INDUSTRIAL TRUCKS Filed Oct. 29, 1956 6 Sheets-Sheet 4 'NVENTOR.

HERMAN N WENDT y/wm ATTY.

July 19, 1960 H. WENDT 2,945,610

METHOD AND MEANS FOR EMPLQYI 3G INDUSTRIAL TRUCKS Filed Oct. 29, 1956 6 Sheets-Sheet 5 FIG. 8

INVENTOR.

HERMANN WENDT ATTY.

July 19, 1960 H. WENDT 2,945,610

METHOD AND MEANS FOR EMPLOYING INDUSTRIAL TRUCKS Filed 001;. 29, 1956 6 Sheets-Sheet 6 FIG. 9b

Fl G. 6 INVENTOR.

HERMANN WENDT y- WM ATTY.

United States Patent f METHOD AND MEANS FOR EMPLOYIN G INDUSTRIAL TRUCKS Hermann Wendt, Hamburg, Germany, assignor to Clark Equipment Company, a corporation of Michigan This invention relates to industrial lift trucks of the type having a telescoping upright mounted at the forward endthereof, and load carrier means mounted on a lift slide which is in turn mounted in tracks of the upright for vertical movement relative thereto, and more particularly it relates to a method and means for employing the load engaging means, such as fork tines, of industrial trucks so as to enable the load engaging means to be manipulated in an extremely novel manner from a position longitudinal of the truck to a position transverse thereof on either the right or left hand side of the truck.

Heretofore, much difliculty and inconvenience has been encountered in the use of such trucks in narrow aisles formed between vertical stacks of materials and in other close quarters, such as is commonly found in warehouses, due to the fact that a lift truck must approach a load to be transported at least approximately at right'angles thereto, so that between two rows of stacks there must be provided a relatively wide passage in order to make it possible for the truck to approach the load.

Equipment for use with lift trucks has been previously constructed which makes it possible to pick up and deposit loads which are stacked or are to be deposited by the side of the lift truck. For example, a construction is known in which a plate is hinged with one of its vertical edges connected to the corresponding side edge of the lift slide (which is mounted for vertical movement in the upright), or adjacent to it, in such a manner that the plate can be rotated in a horizontal plane by pivoting same about its connection. to the side edge of the lift slide. At the opposite edge of this plate a second plate is hinged at its side edge in such a manner that it can likewise be rotated in a horizontal plane, but in the opposite direction. On the second plate is normally mounted a pair of fork tines or other load engaging means. Such construction allows the fork tines to be swung up to 90 to each side horizontally, in relation to the lift slide and upright. With such equipment the load may be picked up and/or deposited either to the right or to the left of the truck, as well as in the driving direction of the truck.

The disadvantage of the above described arrangement is that the fork tines must approach and be removed from the load in a circular movement. Therefore, bale clamps and the like cannot be used, but only the usual fork tines which slip under the load. Because of the circular movement inherent in the use of the above mentioned construction, even fork tines can be used only with special pallets which have only a center support. In other words, the special pallets must have the approximate shape of a flat bobbin for thread. Such pallets are not standard and cannot be used, for example, in pallet conveyers used by the railroads. They are'also unsuitable for large and/or heavy loads, and one-sided loads. Furthermore, loads cannot be removed from vertically stacked rows, nor can they be inserted insuch 2,945,610 Patented July. 19, 1960 "ice inherent circular movement of the fork tines will not allow.

The above mentioned disadvantages have been avoided in another load carrier design which has become known in the industry. In this latter construction, the above mentioned circular movement has been eliminated, and a straight-line sliding movementof the load carrier trans: verse to the driving direction of the truck has been provided for. This has been accomplished by utilizing a horizontal boom which is parallel to the driving direction of the truck and which is slidable on the lift slide in a direction .transverse to said driving direction; in other words, the horizontal boom can slide parallel to itself, actuation thereof being provided, for example, by a chain drive in combination with a double-acting hydraulic press. other load engaging means.

mountable so that by changing the mounting the'equipment can be used on either the right or leftside of the" With such a load carrier, loads which are located to the left of the lift truck can be picked up and then deposited on the left side of the truck, or, if the load engaging means is mounted to the right, such an operation can be accomplished on the right hand side of the truck.

In the latter mentioned construction the load engaging means moves in a straightline, and therefore standard pallets can be used therewith; also, certain loads which can be picked up with standard fork lift .trucks without pallets can also be picked up without pallets with the above mentioned construction. The load units can be taken from tightly stacked rows and can be likewise in: serted for deposit in a relatively small space in closely stacked rows. Furthermore, the fork tines, may be replaced by clamps or other load engaging means which can approach the load in a straight line, which is not possible with the first mentioned construction which is actuated to either side with a circular movement.

However, the primary disadvantage of this load carrier. construction is that it can be utilized only on one side of the truck, and can in no instance be utilized in the driving direction of the truck. If the truck is to be used for work on the opposite side, the load carrier must first be mounted on the opposite side of the boom. For instance, a load cannot be picked up on the right of the truck and deposited on the left thereof or in the driving direction. The picking up and depositing of loads must always be done in the same direction. Ob: viously, this is a considerable limitation on the useful ness of a truck which utilizes such a construction.

Again, a load carrier is known which can execute straight-line lateral movements and can be also rotated from the lateral position, that is, it can lie-pivoted into the driving direction of the vehicle. In this case the load carrier is mounted on a single-arm swing lever which pivots on a vertical axis. This lever can be pivoted by means of a hydraulic rotary slide; by means of a parallelogram guide arrangement it is forced to make a straight-line lateral movement when the load engaging means has been swung into the lateral position. With this load carrier, a load located, for instance, on the right beside the truck, may be picked up and deposited-in a straight-line. However, the load may also be picked up from that side, swung around 90- and deposited" in the driving direction of the stacking truck, or vice versa.

The boom normally carries fork tines or The load engaging means can be secured either to the right or to the left of the boom. Preferably, such load engaging means is de- This latter load carrier has the disadvantage that no change of the working side from right to left or vice versa is possible, not even by remounting. Furthermore, its. construction is very expensive and delicate, and is subject to rapid wear and high maintenance expense. Such a load carrier also protrudes an impractical distance in frontof the lift upright of'the truck. Such protrusion results in greatly reducing the safe lift capacity of any given truck.

Lift trucks have also become known in which the entire upright structure of the truck can be pivoted by means of rotation of trunnion means located on the truck chassis, on which the upright is mounted. These are generally known as slewing-mast type trucks. Such trucks are of very special construction, because the work on the sidecannot be executed by a loadcarrier which can be mounted on any standard lift truck. The manufacturing costs. of such a truck are very high. In the use ofsuch a truck inheres all the disadvantages of the first mentioned swinging load carrier construction.

Finally, a constructionfor a lift truck with a swinging plate of the first mentioned type hasbecome known wherein an additional swinging movement of the fork tinesis provided. The .forks are power driven and are actuatable in parallel relation through a small angle. This latter arrangement involves a further complication ofthe construction, but does not entirely overcome the disadvantages inherent in the resultant circular movement of the fork tines.

It is therefore a primary object of the present invention to overcome the aforementioned disadvantages of prior constructions by providing method and means whichpermits load engaging means of a truck of the type described to be actuated toward or away from a load which is located either to the right or to the left of the truck in a substantially straight-line movement and in various desired alternation.

It is another important object of my invention to provide for vehicles of the type specified, method and means permitting straight-line lateral sliding movement of a load from a stack of such loads, and subsequent swinging of such loads in any desired alternation to the right, to the left, or in the driving direction of the truck, such swinging movements being partial if desired.

It is a further object of my invention to provide a novel load carrier for trucks of the type specified which is movable to any load engaging position within an angle up to 180 without the necessity for remounting the load carrier.

It is a still further object of my invention to provide relatively simple, low cost and extremely novel mechanism for carrying out the above mentioned objects.

Other objects and advantages of my invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

Figure 1 diagrammatically shows the device of my invention in operation in phases a through It;

Figure 1A is a side view in elevation of an industrial lift truck having the device of my invention connected thereto and shown in a side loading position;

Figure 1B is a plan view of Figure 1A wherein the truck is shown diagrammatically;

Figure 2 is a cut-away view in partial section, as seen from the operators station, of the hinged break lever arrangement shown in Figure l to which the fork carrier is.connected;

Figure 3 is ,a plan view of the structure shown'in Figure 2 plus a schematic showing of the guide means for thebreak lever system, illustrated in Figure 1;

Figure 4 is an illustration of the construction shown in' Figure 3 with the break lever system shown in a side loading position;

Figure-5. is an end view in elevationof Figure 3;

Figure-dis a view from the operators station of automatic connection means between the fork carrier and either one of the levers of the break lever system;

Figure 7 is a view taken along line 7-7 of Figure 6;

Figure 8 is a plan view of the structure shown in Figure 6;

Figure 9a is another view of the break lever system in the position shown in Figure 4, and illustrates additional structure for insuring that guide members, to which opposite ends of the break lever system are connected, may be actuated together for the purpose of moving the load carrier laterally with the break lever system in the collapsed position illustrated; and

Figure 9b is a view of the construction shown in Figure 9a, but with the break lever system shown in its extended position.

The present invention intends to solve a special problem, that is, to use a standard industrial lift truck and simply attach to the lift slide a novel type of load carrier means with which all those transportation operations can be carried out which, with previously known constructions, could be carried out only in part. The operations in question are principally the following:

Swinging of the load laterally from a stack, to the right and to the left in any desired alternation, and straight-line movement of the load engaging means by movement of the lift truck in the driving direction.

Straight-line sliding of the load laterally from a stack, following by swinging of the load carrier by as desired, and in any desired alternation to the right or to the left or in the driving direction. The swinging movements can be partial, as desired.

As hereinbefore pointed out, all of the above operations can be carried out without remounting of the load carrier.

Referring now to the drawings, the principal movements of my novel device are shown in Figure I, wherein arrow lines between the individual movement phases (a-h) indicate a portion of the possible movement combinations.

In order to execute the indicated movements, certain couplings must be made between individual movable parts of the machine. These are indicated in Figure 1 by double lines marked K, and, in the description of the example of construction, it will be explained how these couplings are obtained automatically by simple means. In accordance with this invention, the arrangement consists of two levers 2 and 3 which are hinged together and the free ends of which are hinged to guide members 4 and 5, respectively. A load carriage 16 is hinged to the common joint of levers 2 and 3 and is adapted to swing horizontally. As illustrated, the load engaging means comprises the usual pair of fork tines which are secured to the carriage 16 in known manner. All movements of the carriage are executed as a result of movement of the guide members 4 and 5 along a guide track 1.

Phase a of Figure 1 illustrates the load carrier in its basic position relative to the lift truck, in which position the truck can be utilized in a well known manner, as with the usual forwardly projecting fork tines. By moving the guide member 5 toward guide member 4, the carriage 16 passes via the position illustrated in phase 5 into the position illustrated in phase c. Now the carriage may be moved either laterally, as shown in phase d, or, by sliding the guide members 4 and 5 apart, it may pass the position shown in phase g and return to the basic position. However, the carriage may also pass from the position shown in phase d via the position shown in phase 11 into the basic position of phase a. In this instance, contrary to the movement between phases c-g-a, the load carrier is swung largely within the area of the vehicle, so that only a very narrow passage is required. This means that the stacking space can be better utilized because the stacked rows can be placed closer together.

In a similar manner, the load carrier can be swung -.to the right via phase positions-a-e-f and from;.thc posh tion shown in phase 7 may be actuated in a straight-line transverse to the driving direction of the vehicle, as illustrated in movement phases c--d, but in an opposite sense thereto. I

All of the described movements can be combined 'in any desired alternation, so that the greatest possible freedom in the use of the equipment is obtained. Such'a multiplicity of movements within one operation is required only in exceptional cases.

Referring now to Figures 1A and 1B, 1 have indicated an industrial lift truck generally at numeral 50. My invention is well adapted for use with such avehicle. This vehicle is of a well known type and includes a body portion 52 which is mounted on four wheels in the usual manner. An operators station is indicated generally at numeral 54, and includes a steering wheel for operating the rear wheels of the truck, an operators seat, and various controls, not shown, for operating the truck and the device of my invention which is associated therewith.

A vertically disposed telescopic mast structure is lo cated at the front end of the body portion of the truck and is indicated generally by numeral 56. Mast structures of the general type indicated are known and need not be described in detail herein. Generally, the mast structure 56 includes an outer guideway formed by a pair of channel members 58 and an inner slide member 60 which telescopes within the outer guide structure and which is formed by a pair of laterally spaced I-beams nested within the outer guide structure,

The plate member 18, to which the device of my invention is connected, is supported for vertical movement relative to the inner slide member 60 by means of a known bracket and roller assembly 62 associated with each one of the I-beam members of the inner slide structure. an hydraulic hoisting device 64 by means of lifting chains 66. This construction is also well known in the art and need not be amplified herein.

A principal advantage of my invention lies in the fact that with one and the same lift truck, without any' remounting of the carrier and without the exchange of any parts, all stacking work which can possibly occur can be accomplished. For instance, a lift truck which utilizes my device may work for days or hours as a standard lift truck, then as a swinging lift truck, and finally as a side shifting lift truck, either to the right or to the left or alternatingly to the right and the left and straight ahead. 7

As will be later shown, the load carrier of this invention can be considerably simplified if it is to be used only as a universal transportation vehicle, without the requirement for remote control of the positions of the carriage 16.

The underlying concept of the invention has already been explained in connection with Figure 1. The fork tines or other load engaging means are mounted about a vertical hinge or pivot connection of two levers which can swing horizontally in the hinge, and the opposite ends of which can likewise swing horizontally on guide members which are movable transversely to the driving direction of the vehicle.

In order to have the carriage 16 fixed for the intended purpose in all positions, it must be coupled with a particular one of the guide members 4 and 5 when such guide members are moved horizontally. According to this invention this is done by an automatic catch which will be described hereinafter.

In addition, it is necessary that the axes about which the opposite hinged ends of the levers 2 and 3 pivot will be in substantial alignment when the guide members 4- and 5 are adjacent each other as in Figure 4, and that when in such position the levers 2 and 3 (which have been brought together to 0) cannot swing in relation to the guide track L In other words, the doubled-up levers 2 and 3 must function as a solid boom, which re- The plate member 18 is operatively connected to sult can be obtained by ineans to be des'cribed herein the somewhat schematically illustrated construction shown in Figures 2-5, as well as in Figures 6-9, is exemplary only, and that numerous deviations from the illustrated embodiment of my invention may be made without departing from the scope thereof.

Referring now to Figures 2-5, the carriage 16 is equipped at both its upper and lower edges with :1 lug 9. The two lugs 9 are hinged coaxially with the hinge 8 of levers 2 and 3, so that the carriage can swing in a horizontal plane about the axis of vertical hinge 8 at any desired elevation of the carriage relative to the tele scoping upright of the truckwhenever the levers 2and 3 have an enclosed angle less than The levers 2 and 3 together essentially comprise a hinge having long flaps or sides which are connected at the adjacent ends thereof to the hinge joint 8. The free or opposite ends of levers 2 and 3 are hinged at 11 and 12 to the guide members 4 and 5 which are adapted to slide on, at or in the guide track 1 in a sliding or rolling manner and in a direction transverse to the longitudinal axis of the vehicle. The levers 2 and 3 are hinged to the guide members 4 and 5 in such a manner that the swing axes of the two joints are aligned when the guide members are adjacent each other, as in Figure 4.

Located at the opposite ends of the guide track 1 are stops 28, against which the guide members 4 and 5 rest when levers 2 and 3 have been extended to enclose an angle of 180 (Figure 3). In this basic position the carriage 16 faces in the driving direction of the vehicle. The coaxial alignment of the axes of hinges 11 and 12 can be obtained by different manners of constructio-n For example, as best shown in Figures 2 and 5, the joints 11 and 12 on the guide members 4' and 5, respectively, are vertically spaced in relation to each other in such a manner that the one joint is registrable with spaces provided in the other joint. A construction must be provided such that in the transition from the basic position to the broken position of levers 2 and 3, the levers break toward the outside in a direction away from the guide track 1 and plate member 18 when the guide members 4 and 5 are brought together. i This can be accomplished, for example, by resting the joint 8 in the stretched position of the levers against a resilient member, not shown, on plate 18, which may comprise a simple leaf spring. By such an arrangement the joint 8 will be automatically broken in the proper direction when the guide members are brought together. Such a construction also has the advantage that in the transition from a lateral position into the basic position, the carrier 16 will be brought to rest against a resilient member.

In order to solve the problem under consideration, the levers 2 and 3 must have a fixed position when they are brought together to 0, and this may be obtained in a simple manner as shown in Figures 9a and 9b. Each one of the two levers 2 and 3 has at its joint at the respective guide member, a lug 26 which rests against a surface of the respective guide member when the angle of 0 has been obtained. This construction allows the lever system to become rigid when in such position, as intended.

In addition, as mentioned hereinabove, it is necessary to provide means for automatically connecting the carriage 16 to one of the levers or guide members, as required for the proper operation of the device, and as diagrammatically indicated in Figure 1 by the double lines K. In Figures 6, 7 and 8 there is illustrated a structure adapted to achieve this result. On the guide members 4 and 5 suitable catches are mounted in vertically spaced relation to each other to achieve such result; The arrangement consists of a double-arm lever 20 with the arms 20 and 20" pivotably mounted on the pin 21 and is limited by suitable stops. The lever arm 20 is adapted to engage in a slot 22 the pin 23. A spring 19 normally urges slot 22 of lever 20 into engagementwith pin 23. Each pin 23 is, for example, mounted on a lug 24 of the carriage 16 in such a manner-that when the carriage is in its basic position, the axis of each pin 23 is aligned with the joint axis of the respective guide member, as illustrated. The position of carriage 16 and of the fork tines is thus fixed. A pull member 15 is connected to the lever arm 20" which is located on the opposite side of pivot pin 21 from arm 20, and

is adapted to actuate the one guide member in the direction indicated by the arrow Z when the one guide member is moved toward the other guide member for the purpose of swinging the fork tines.

In this operation the carriage 16 must rotate suitably on the center of rotation of the fixed guide member 5. By means of the force exerted on lever arm 20," by member 15, the lever arm 20 is pivoted about pin 21 against the pressure of spring 19 such that the opposite arm 20' releases said pin. However, inasmuch as the pivot pin 23 at the opposite end of carrier 16 is still held in position by the double-arm lever 20 associated therewith (which lever is not subjected to any pull) carrier 16 is forced to retain its position parallel to the hinged lever 3, i.e, it must swing to the right of the truck.

In Figure 6 is illustrated the above described locking means, which is located in the upper left hand corner of the carriage 16, as viewed from the operators station on the lift truck, whereas Figure 8 is a plan view of the device shown in Figure 6, and Figure 7 is a view in section along line 7--7 in Figure 6. The embodiment of the locking or catch means as illustrated in Figures 6, 7 and 8 should be considered as exemplary only inasmuch as, for example, other means known to persons skilled in the art may be provided for making the pin 23 releasable under spring action. In the above described embodiment the pin 23 in relation to lever arm 20 can be swung into the slot 22 under spring action within narrow limits. This action takes place only when the carriage 16 approaches the guide member on the side on which the catch is intended to act, i.e., when carriage 16 is brought into the basic position by extending guide members 4 and 5. Since during such a movement phase the pull member 15 acts in a direction opposite to that indicated by the arrow Z, lever 20' cannot bypass pin 23; rather, the pin is moved along the sloping surface of lever arm 20' and finally snaps into slot 22 when the extended or basic position of levers 2 and 3 has been attained.

According to the exemplary embodiment shown in Figures 6 and 8, the pin 23 is mounted on a swinging lever 25 which is under spring pressure and which protrudes through a slot in lug 24. This arrangement may be sim plified by hinging the pin 23 directly to the carrier 16 with a spring actuated lever.

Finally, for the solution of the entire problem, provision must be made for holding in position that end of carriage 16 which is adjacent the guide track 1 when the levers 2 and 3 are in the swung-out or collapsed position shown in Figures 4 and 9a, if it be desired to simultaneously actuate guide members 4 and 5 for the purpose of moving the transversely extending fork tines laterally, as from phase c to d in Figure 1. In this case, if no such holding device were provided, the effect of the pull 15 acting on the guide member which is coupled to carriage 16 when the fork tines are actuated into the basic forward position, would open just that catch which must remain closed in order to preserve the correct carrier position for lateral movement thereof along the guide track 1.

In Figures 9a and 9b there is illustrated a simple means for preventing any such undesired opening of the catch. In Figure 9a, for example, the catch lever 20 is mounted on the top of the left guide member 4 (as shown in Figure 7), and atop the guide member 5 is mounted astop member 27 which, when the guide members are adjacent each other, rests against lever 20 in such a manner that the lever cannot change its position even though the pull 15 acts on lever arm 20". A similar device, not shown, is mounted at the lower portion of the guide member 4 which, in a corresponding manner, arrests movement of swing lever 20 at the underside of guide member 5, thereby preventing movement of guide member 5 when a pull is exerted thereon in the opposite direction.

The movement of the guide members can be accomplished in any desired manner by previously known means. It is not material in what manner the pull of member 15 is produced. For example, the power may be furnished by a suitably mounted double-acting hydraulic press, as has been previously done on known equipment, with a lateral sliding movement. Preferably, two such presses are provided at the plate 18, the one acting on the pull member 15 for guide member 4 and the other on the pull member 15 for guide member 5. With such an arrangement, the two presses may be controlled by means of four valves combined into one bat; tery, each one controlling three paths. Each one of the two chambers of each one of the two presses can be connected, as desired, to the pressure pump and to the discharge reservoir, and each chamber of one press can be connected to its other chamber, when the press is to run idle. The valves may, for instance, be sliding piston valves, controlled by the cams of a program cam shaft; all required movements can in such a case be executed by means of a single control lever.

As hereinbefore mentioned, only rarely are all possible movements of the fork tines required in any odd sequence. Therefore it suffices in many instances to exercise control of the swinging movement of the fork tines by means of a single handle, and the control of the sliding movement by means of another handle. This, of course, would greatly simplify the control arrangement.

Finally, there may be instances when it sutfices to make only the sliding movement to the right or to the left, while the pivoting action of the fork tines is used only to move the load carrier from the one side to the other or to place it into its basic position when the truck is to be used as a standard lift truck. In such a case, it is unnecessary to provide power means, as a hydraulic press, for pivoting the carriage 16 and the fork tines; instead, such pivoting movement may be executed by hand. Also, the automatic catch or locking means illustrated in detail in Figures 6, 7 and 8 would not be required in such a case, and can be replaced by a simple hand operated linkage. Also, a single double-acting hydraulic press will sufice in this case which, in known manner, executes only the lateral sliding movement.

Even with such a simplified construction as above outlined, a lift truck is still enabled to pick up a load, for instance on the right of the truck and deposit it to the left thereof, and vice versa, or to change from one side into the driving direction of the truck, when this is desired in exceptional cases. In such cases the pivoting movements from the one operating position into the other, must be executed by hand.

Although only one embodiment of my invention has been described in detail, it will be understood that numerous changes might be made in the construction, form and arrangement of parts without departing from the scope of the invention.

I claim:

1. In combination, a guide means, hinged means having elongated flaps or lever arms which are pivotally joined together at adjacent ends thereof, the opposite end of each of said lever arms being operatively connected to said guide means, said operative connection including means about which each of said lever arms may pivot relative to said guide means and at least one of said operative connections including a guide member which is movable with the respective end of one of said lever arms in a direction longitudinal of said guide means, carriage means pivotally connected to said hinged means adjacent the joined ends thereof, and means spaced from said joined ends for securing the carriage means to at least one of said lever arms.

2. An attachment for an industrial truck comprising means defining a guide track, a pair of horizontally extending swinging lever means, vertical pivot means connecting said lever means together at one end each, the opposite ends thereof being operatively connected to said guide track in such a manner that each of said lever means is cantilevered from the guide track and is pivotable about the respective opposite end thereof and each said opposite end is actuatable longitudinally of said guide track, and load carried means operatively connected to the vertical pivot means.

3. An attachment for an industrial truck comprising load support means operatively connected to said truck at one end thereof, a break lever system which includes a pair of levers connected at adjacent ends thereof for relative pivotal movement of one lever relative to the other and means operatively connecting the ends of said leversopposite said adjacent ends to said support means for outwardly directed pivotal movement of said levers relative to said support means, at least one of said connecting means including means slidable longitudinally of said support means for pivoting said levers in opposite directions about the connected adjacent ends thereof, and load carrier means connected to at least one of said levers for movement therewith.

4. An attachment as claimed in claim 3 wherein the said opposite end of each of said levers is operatively connected to said load support means such that either said opposite end may be selectively actuated longitudinally of said load support means.

5. An attachment as claimed in claim 3 plus means connecting said load carrier means to said one lever and wherein said connecting means connects the load carrier means to that lever opposite the lever which is actuatable at one end thereof longitudinally of said load support means.

6. An attachment as claimed in claim 4 plus means automatically securing the load carrier means intermediate the ends of one of the levers during actuation of the opposite end of the other lever longitudinally of said load support means.

7. An attachment for industrial lift trucks comprising an upright frame located adjacent one end thereof, load supporting means elevatable relative to said upright frame and extending transversely of the truck in a plane parallel to the plane of the upright frame, hinged means having the opposite ends thereof operatively connected to the load support means for pivotal movement relative thereto, at least one of the opposite'ends of said hinged means being selectively actuatable toward and away from said other opposite end in a direction longitudinal of said load support means and transversally of the truck,'whereby when said longitudinally movable opposite end is actuated to a position adjacent the said other opposite end the hinged means acts as a boom extending longitudinally of said truck and when said longitudinally movable opposite end is actuated to its furthermost position from said other opposite end said hinged means functions as a supporting means which extends transversely of said truck and longitudinally of said load support means.

8. An attachment as claimed in claim 7 plus load carrier means operatively connected to said hinged means in such a manner that actuation of the one opposite end of said hinged means longitudinally of the load support means is capable of automatically effecting pivotal movement of said load carrier means with one of the'sides of said hinged means and about the other opposite end thereof. 7

9. In an industrial lift truck having an upright construction located adjacent one end thereof and means elevatable relative to said upright construction, an attachment supported by said elevatable means and normally extending transversely of said truck comprising mean-s hinged intermediate its ends and forwardly of the elevatable means and operatively connected to the elevatable means adjacent its opposite ends for pivotal movement, one of the pivoted end connections of said hinged means being actuatable in a direction transverse to the truck and longitudinal of said elevatable means, said pivoted end connections of said hinged means being so constructed and arranged that actuation as aforesaid of one thereof is capable of effecting a variation in the included angle formed between the sides of said hinged means of or less to 0 or more as said one pivoted end connection of said hinged means is actuated from a position at or near one side of said elevatable means to a position at or near the opposite side thereof.

10. An industrial truck attachment as claimed in claim 9 plus load engaging carriage means secured to that side of said hinged means which is opposite the side actuatable transversely of the elevatable means.

11. An industrial truck attachment as claimed in claim 9 wherein either opposite end of said hinged means is selectively actuatable transversely of the truck, and load engaging carriage means extending forwardly of said hinged means and adapted to be connected to either side thereof.

l2."An industrial truck attachment as claimed in claim 11 wherein said hinged means comprises a lever system breakable forwardly of said truck at the hinged connection thereof when one of the opposite ends thereof is actuated'transversely of the truck in a direction to approach the other opposite end thereof, said pivoted opposite'ends thereof being so constructed and arranged as to be actuatable into overlapping relation with each other, whereby said hinged means is functionable as a forwardly extending boom. I

13. An industrial truck attachment as claimed in claim 11 wherein said carriage means is normally coupled to that side of said hinged means opposite the side which is actuated transversely of the truck, whereby said carriage means is swingable from a forwardly directed position to a transversely directed position at either side of the truck as'one of the sides of the hinged means is actuated transversely of the truck.

14. An industrial truck attachment as claimed in claim 11 wherein said carriage means is connectable to that side of the hinged means which is actuated transversely of the truck.

15. For use with industrial trucks, an attachment connected to said truck adjacent one end thereof comprising means normally extending transversely of the" truck mounted, for pivotal movement about either opposite end of itself and constructed for breaking action intermediate its opposite ends, carriage means normally connected to the first mentioned means both adjacent the breaking location thereof and also on opposite sides of said breaking location, a selected one of said opposite ends being actuatable toward the other opposite end whereby to eifect a breaking action of said first mentioned means one of said connecting means between said first mentioned means and said carriage means being so constructed that it is releasable from its connection to said first mentioned means when one of said opposite ends of said first mentioned means is actuated toward the other said opposite end thereof.

16. For use with industrial lift trucks, an attachment comprising a lever system breakable intermediate the ends thereof, either of said ends being actuatable toward or away from the other of said ends to effect a forwardly extending boom-likestructure or a transversely extending carrier structure, respectively, and said opposite ends of said lever system being also actuatable together transversely of the truckfollowing actuation of one of said opposite ends into adjacency with the other of said opposite ends to form said boom-like structure, and load engaging means coupled to said leversystem in such a manner that the various selectable movements of the opposite ends of said lever system may efiect a plurality of positions of the load engaging means including positions'thereof extending outwardly from either side of the truck and also forwardly in the direction of travel of the truck, the above positions of said load engaging means being selectable in various alternations as desired.

17. An attachment as claimed in claim 16 wherein the said opposite ends of said lever system are each ,connected to a guide member, and guide track means mounted transversely of the truck and constructed to receive each of said guide members in such a manner that each of said guide members is actuatable longitudinally of said guide track.

l8. Anattachment as claimed in claim 17 wherein the opposite ends of said lever'system are so constructed that the pivot axes thereof may be actuated into substantial alignment with each other when one of said guide memhers is actuated into adjacency with the other;

19. An attachment as claimed'in claim 18 wherein the said opposite ends of said lever system each includes stop means which are adjacent to the respective ,guide members when said pivot axm are brought into substantial alignment.

'20. An attachment as claimed in claim 17 wherein means for coupling the load engaging means to the lever system comprises means mounted on each of said guide members, means mounted adjacent each opposite end of said lever system and engageable with said mounted means, each of said mounted means being mounted on its respective guide member such that each said engageable means is releasable from its associated mounted means during actuation ofsuch guide member in a direction transverse of the truck.

21. An attachment as claimed in claim 16 wherein the means which effectively connects the load engaging means to the lever system comprises locking means associated with said lever system and lockable means connected to the load engaging means and engageable by said locking means when said lever system is in its extended position transverse of the truck, said locking means being disengageable from said lockable means when one end of said lever system is actuated transversely of the truck.

22. A load handling device for use with industrial vehicles comprising load support means connected to the vehicle and extending transversely thereof, load carrier means for engaging loads, and position control means connecting said load carrier means to said load support means and being supported by the load support means for guided movement relative thereto, said position control means being locatedvnormally transversely of the vehicle in .a plane generally parallel to the plane of the load support means and articulated to be actuated from said transverse location to extend forwardly of the vehicle as a boom in a plane generally transverse to the plane of the load support means, and said position control means being actuatable transversely of the vehicle in a straight line motion along said load support means when extending forwardly thereof as a boom.

23. A load handling device as claimed in claim 22 wherein means connects said load carrier means to said position control means such that movement of said load carrier means from ,a forwardly directed load engaging position to a load engaging position transverse to the forwardly .directed position is executed during movlement of the position control means from a plane generally 12 parallel to the load support means to a plane generally transverse to the load support means.

24. A load handling device as claimed in claim 23 wherein following movement of the load carrier means to a transverse load engaging position, the load carrier means may be actuated together with the position control means transversely of the vehicle in straight line motion.

25. A load handling device for use with industrial vehicles comprising load support means connected to the vehicle and extending transversely thereof, load carrier means, and load carrier position control means connecting said load carrier means to said load support means and being supported by the load support means for guided movement relative thereto, said position control means being articulated in the central portion thereof and forwardly of the load support means such that it may be located in a plane generally parallel to the plane of the load support means and articulated to extend forwardly of the vehicle as a boom in a plane generally transverse to the plane of the load support means and then actuated transversely of the vehicle in straight line motion along said load support means while extending forwardly thereof as a boom.

26. A load handling device as claimed in claim 25 in which means are provided to connect the load carrier means to the position control means in such a manner that the load carrier means follows selected movements of the position control means thereby rendering the load carrier means operable to engage a load located forwardly of the vehicle in the direction of travel thereof or located outwardly from either side of the vehicle, said load carrier means being actuatable with said position control means transversely of the vehicle in straight line motion to either engage or deposit a load as aforesaid which extends outwardly from either side of the vehicle.

27. A method of manipulating the load engaging means of a materials handling truck from a position longitudinal of the truck to a position transverse thereof, the load engaging means being attached to one end of the truck by an articulated device which is adapted to support the load engaging means for swinging movement therewith, which comprises the steps of securing the load engaging means to one side of the articulated device when the device is open and extends transversely of the truck, of closing the device adjacent one side of the truck to form a forwardly extending boom and to swing the load engaging means with that side of the device to which it is secured to a position transverse of the truck, and of moving the boom and the load engaging means secured thereto transversely of the truck to a position adjacent the opposite side thereof.

28. The method of manipulating the load engaging means of a materials handling truck as claimed in claim 27 plus the step of opening the hinged device from said position adjacent the opposite side of the truck by moving one side of the hinged device toward said one side of the truck, which causes the load engaging means to swing with that side of the hinged device to which it is secured from its position transverse of the truck to its initial position.

29. The method of manipulating load engaging means, such as fork tines, of an industrial lift truck so as to automatically engage a load at one side of the truck and deposit it forwardly thereof, the load engaging means being supported for swinging movement in a horizontal plane by the joint of a hinge device which is connected to one end of the truck for guided movement transversely of the truck, which comprises the steps of driving the truck to a position wherein a load is adjacent one side of the truck at one end thereof, moving one side of the hinge device transversely .of the truck into a position of adjacency with the other side of the hinge so as to project the hinge device longitudinally of the truck .as

- l3 a i a boom and cause the load engaging meansto swing with one side of the hinge device toa position wherein the load engaging means extends transversely of'the truck and engages the underside of the load, raising the load with the load' engaging means,moving the boom-like hinge device transversely of the truck with the load engaging means and load to a position adjacent the opposite side thereof, moving the one side of the hinge device to a position adjacent the side of the truck at which the load was engaged to open the closed hinge device and swing the load engaging means with its load to a position longitudinal of the truck, and transporting the load to a given location for deposit.

30. The method of manipulating load engaging means, such as fork tines, of an industrial lift truck so as to automatically engage a load at one side of the truck and deposit it on the opposite side thereof when the load engaging means is connected for swinging movement in a horizontal plane to the joint of a hinge device which is connected to one end of the truck for guided movement transversely thereof, which comprises the steps of moving the truck to a position wherein a load is adjacent said one side of the truck at the one end thereof, closing the open hinge device to form a boom by moving one end thereof transversely of the truck into a position of adjacency with the opposite end thereof, causing the load engaging means to swing with one side of the hinge device from a position longitudinal of the truck to a position transverse of the truck as the hinge device is manipulated from an open to a closed position, engaging and lifting the load at the said one side of the truck with the load engaging means, reopening the hinge device by reversing the aforesaid closing operation thereof, moving the side of the hinge device opposite to that moved for engaging the load transversely of the truck into a position of adjacency with the other side of the hinge device to form a boom adjacent the said opposite side of the truck, causing the load engaging means and load to swing with that side of the hinge device toward which the other side thereof is moved, and depositing the load adjacent the said opposite side of the truck.

31. In an industrial truck, an upright mast construction fixed transversely of the truck adjacent one end thereof, load support means connected to the upright mast for elevation relative thereto, load carrier means for engaging loads, and articulated position control means connecting said load carrier means to said load support means and being supported by the load support means for guided movement relative thereto, said position control means being located normally transversely of the vehicle in a plane generally parallel to the plane of the load support means and being actuatable to extend forwardly of the vehicle as a boom in a plane generally transverse to the plane of the load support means, and said position control means being actuatable transversely of the vehicle in a straight line motion along said load support means when extending forwardly thereof as a boom.

32. In an industrial truck, an upright mast construction fixed transversely of the truck adjacent one end thereof, load support means connected to the upright mast for elevation relative thereto, load carrier means for engaging loads, articulated position control means connecting said load carrier means to said load support means and being supported by the load support means for guided movement relative thereto, said position control means being located normally transversely of the vehicle in a plane generally parallel to the plane of the load support means and being actuatable to extend forwardly of the vehicle as the boom in a plane generally transverse to the plane of the load support means, and said position control means being actuatable transversely of the vehicle in a straight line motion along said load support means when extending forwardly thereof as a boom, and means connecting said load carrier means .14.... to said position control means such that. movement of said load carrier means from a forwardly .directed load engaging position to a load engaging position transverse to the forwardly. directed position is executed .during movementof the position control means from a plane generally parallel to the load support means to a plane generally transverse to the load support means.

33. In an industrial truck, an upright mast construction fixed transversely of the truck adjacent one end thereof,

load support means connected to the upright mast for elevation relative thereto, load carrier'means for engaging loads, articulated position control means connecting said load carrier means to said load support means and being supported by the load support means for guided movement relative thereto, said position control means being located normally transversely of the vehicle in a plane generally parallel to the plane of the load support means and being actuatable to extend forwardly of the vehicle as a boom in a plane generally transverse to the plane of the load support means, and said position control means being actuatable transversely of the vehicle in a straight line motion along said load support means when extending forwardly thereof as a boom, means connecting said load carrier means to said position control means such that movement of said load carrier means from a forwardly directed load engaging position to a load engaging position transverse to the forwardly directed position is executed during movement of the position control means from a plane generally parallel to the load support means to a plane generally transverse to the load support means, and means for actuating the load carrier means and the position control means in a straight line motion in either direction along said load support means when said position control means is located in a plane generally transverse to the load support means;

34. An industrial truck comprising an upright mast construction connected transversely of the truck adjacent one end thereof, load support means connected to the upright mast for elevating movement therein, load carrier means, and position control means connecting the load carrier means to the load support means and being supported by the load support means for guided movement relative thereto, said position control means being articulated in the central portion thereof and forwardly of the load support means such that it may be located in a plane generally parallel to the plane of the load support means and articulated to extend forwardly of the truck as a boom in a plane generally transverse to the plane of the load support means and then actuated transversely of the truck in straight line motion along said load support means while extending forwardly thereof as a boom.

35. A method of manipulating the load engaging means, such as fork tines, of an industrial lift truck having an upright mast construction located at one end of the truck from a position longitudinal of the truck to a position transverse thereof, the load engaging means being attached to the upright mast by a device which is adapted to be opened and closed about a pivot means which is located centrally of the truck when the load engaging means extends longitudinally of the truck and which supports the load engaging means at the pivot means, which comprises the steps of securing the load engaging means to one side of the device when the device is open at which time the load engaging means extends longitudinally of the truck, and of closing the device adjacent one side of the upright mast to form a boom which extends forwardly of the truck and its mast whereby to swing the load engaging means with that side of the device to which it is secured to a position wherein the load engaging means extends transversely of the truck.

36. The method of manipulating a load engaging means as claimed in claim 35 plus the step of actuating the boom formed by the closing of the device transversely of the truck and mast to a position adjacent the opposite side of the truck and mast.

37. The method of manipulating a load engaging means as claimed in claim 36 plus the step of opening the device from said position adjacent the opposite side of the truck and mast by moving one side of the device toward said one side of the truck, which causes the load engaging means to swing with that side of the device to which it is secured from its position transverse of the truck to a position longitudinal thereof.

References Cited in the file of this patent UNITED STATES PATENTS 636,445 McCabe et al. Nov. 7, 1899 

